Radio signaling system



Aug. 30, 1932. F. H. KROGER RADIO SIGNALING SYSTEM Filed May 22, 1926 ammo/44 C012 FRED HUTTON KROGER 3% his (mime/ 9} Patented Aug. 30, 1932 .UITED STATES PATENT oFFic FRED HUTTON KROGER, OF BROOKLYN, NEW YORK, ASSIGNOR TO RADIO CORPORATION OF AMERICA, A CORPORATION OF DELAYVARE RADIO "SIGNALING SYSTEM Application filed May 22, 1926. Serial No. 110,895.

"My invention relates to radio transmission systems, and particularly to means for stabilizing the frequency thereof.

An object of my invention is to provide a radio signaling system having means for maintaining superior accuracy of radiation frequency therefrom.

An object ofmy invention is to provide a radio frequency generator having a master oscillator and means for maintaining the frequency-of generation thereof constant.

Another object of my invention is to provide a radio frequency generating system having a master oscillator, a power amplifier, an

antenna system and means for maintaining the frequency of the master oscillator constant. I

Another object of my invention is to provide a radio frequency oscillation generating system having a master oscillator an antenna and means for preventing change in the antenna constants from influencing the frequency of the master oscillator.

Another object of my invention is to provide a master oscillator and power amplifier in combination with reverse feed-back means therebetween.

Another object of my invention is to provide a system comprising a plurality of trlode vacuum tubes, means for maintaining self oscillation of some thereof, and means for preventing any oscillatory tendency in others thereof.

Another object of my invention is to provide means in combination with a group of parallel connected triode vacuum tubes for segregating various portions of the group to various respective functions thereof.

In the prior art of the development of radio frequency oscillations by means of triode vacuum tube generators, attempts have been made to provide a master oscillator to determine the frequencyof oscillation, a power amplifier to supply the necessary energy and an antenna to radiate the oscillations. Difficulty has been experienced, however, in maintaining a constant frequency in the master oscillator, because of the tendency for electrical reaction to occur from the power amplifier to the master oscillator, either atfrequenter oscillator in combination with a power amplifier have lead to very complicated, unstable, and unsatisfactory systems.

My invention provides a very simple circuit in which all of the triodes of the system may be connected substantially in parallel, particularly with respect to the filaments and grids thereof and in addition means for segregating a part of the group to the function of the production of oscillations and the others of the group to the function of amplification at the generated frequency.

My invention further provides means for preventing reaction from the amplifier group to the oscillator group.

Other objects and structural details of my invention will be apparent from the following description when read in connection with the accompanying drawing, wherein:

The single figure is a diagrammatic representation of circuits and apparatus embodying my invention;

In the figure a group of triodes 1 to 8 inclusive are provided. The filaments thereof are connected in parallel by the conductors 9 and 10, which are connected to a transformer 11, which in turn is connected to a source of energy not shown. The grids of the triodes 1 and 2 are connected directly in parallel and through a condenser 12 to a lead 14. The grids of the triodes 3 to 8 inclusive are likewise connected directly in parallel and through a condenser 15 to the same lead 1 thus bringing all the grids substantially in parallel. Inductive grid leak combinations 16 and 17 are likewise provided and connected through the lead 18 to a grid biasing means 19.

A tank circuit 21 is provided comprising a variable inductance 22 and capacitance 23. A conductor 24 is connected to a mid point tap upon the inductance 22 and to the filament circuit conductors 9 and 10. The

grid conductor 14iis likewise connected to a tap near one end of the inductance 22.1

The plates of the triodes l and 2 are connected in parallel and through a condenser 25, to a tap upon the opposite end of the in ductance 22. The anodes of the triodes l and 2 are supplied ,with current througha choke coili26 from a source (not shown), connected 2 is condenser 34 to another 'tap upon the induc- .to terminal 27 This assemblage ofelements with triodes 1 and 2 produces an oscillation generatorwacr tem.

The plates of triodes 3 to S'inclusive are likewise connected together in parallel, and

cording to the well known Hartley sys:

through an inductance 28 to-the terminal andpthe plate current supply, The induck tance 28 is'coup'led to an inductance 29. which in" turn may be connected in the aerialcircuitby means ,of a suitable switching ar-l rangemeiitiO, whichinay comprise, as shown, an auxiliary inductance 31, an a'erial 32 and ground 33 with theusual antenna meters in" circuit. The plate circuit of the triodes 3jto 8 inclusive is likewise connected through a tance -22;

Gr dbiasing means, audio frequency interrupting means, an'd'lreymg means well known in the art be. provided as iiifdi-" 1 cated at butneed' not be described here in detail. I Y

- In the operation of my device the triodes land 2, in combinationwiththe inductance 22" and'capaci'tance 23 and the circuit connections shown, function as the'typical Hartley oscillationsystem according to the broad systein disclosed by Armstrong. wOscilla'tory energy isalso transferred from. the induce tance 22 through the conductor 14 and the condenserlti to thefgrids of the triodes 3 to 8 inclusive, causing the-customary effect upon the electron streams thereth'roiigh, and" the.

repeating and amplifying of'those oscillations in the usual mannern The amplified oscillations, then are transmitted to'the aerial circuit in the usual fashionby the coupling between the coils 28 and29. p

Thefsystem so far described would, in the" absence-of other elements for stabilizing it be subject-to the serious disadvantage that the am-plifying triodes 3 to 8 inclusive are 'sub- Jectv to reaction from the antenna circuit whichmay vary with swinging of the antennalead, or, in, ship service, with rolling of'the ship. This reaction maybe transmit-v tedlthrough the grid circuits of the tubes 3 'tol'S inclusivetothe inductance22 causing. a

change in oscillation frequency therein which .inaybe extremely troublesome when the signals are receivedat a remote point, 7 V

c invention provides in combination with the previously described structure a neutralizing condenser 34:,connected between the anode circuits 1 of the 1 power] amplifying erator for preventing the 'ergy of undesired frequencies.

very constant frequency maintained therein. j 'Wliile I haVQ'SllOWH'bHt one embodiment of myv iiivent oi inthe foregoing drawing and description it is capable of various modifica- I tioiis therefrom without departing from the spirit thereof,and it is desired therefore that only suchlimitations-shall be imposed thereon as-are required by the prior art or indicated bytheappended claimsi, 7 l

v I claim as my invention: a

' 1 radio signaling systemfconiprisiiig 7 an oscillationgenerator,v an oscillation ainplifier amplifyingoscillations generated' by said generator, and an oscillation 'neutraliz e, ing circuit connecting the. )i1tp utfcircuit; of

said amplifier to a cold electrode ofsaid gene eneration of ,en-j

A radio signalings'ysteln omprisestriode, anv oscillatory circuit comprising ductaiice and capacitance and en rgy supply.

means for said triode andsaid oscillatory cir.-'

cuit, whereby oscillations are generated, an additional triode connected to said oscillatory circuit, means for supplying energy tojsai'd second triode, an output circuit for-said sec- 0nd triode, and means compris ng a capacity connecting the output vlof said second ti'lOdQ to said oscillatory circuit for preventing self oscillation of said second-triode.

p 3. A radio signaling system comprising, an oscillation generat ng means, an oscillation amplifying means for amplifyingoscillations; generated by said oscillation generating means, an oscillatoryfcircuit ,fqrming a part of 831d. oscillat on generating "means and a neutralizing capacity connecting the output:

offlsaid oscillation amplifying mea -and said oscillatory circuit for preventing selfoscillation in said oscillation amplifying:

means.

it, Aradio signaling systemcornprisingan oscillation generating means, an oscillation ainpl fyingjmeans for amplifying oscillations generated byisaid oscillation generating means, a'closed oscillatory circuit for'ining a parto'f said oscillation generating; means,

and a capacity connection fron the'output of said oscillation amplifying means to. sa d closed oscillatory circuit forpreventing selfoscillation in said oscillation amplifying means. 1 c

[5; A radio signaling systenicomprisingqa group of triodes,imeans for causing oscillations to be produced in a portion of said group of triodes, an oscillatorytank' circuit ccnnettcd Withs'aid portion of said groupot triodes, a second portion of said group of trition of said group of triodes.

6. A radio signaling system comprising, a group of trlodes, means for causing oscillations to be produced in a portion of said group of triodes, an oscillatory circuit associated with said portion of said group of triodes, means for amplifying the oscillations produced in said first portion of said group of triodes, said amplifying means including the second portion of said group of triodes, and a capacity connecting said oscillatory circuit and the output of said second portion of said group of triodes for preventing selfoscillation in said second portion of said group of triodes.

7. A radio signaling system comprising, an oscillation generating means, an oscillation amplifying meansfor amplifying oscillations'generated by said oscillation generating means, an oscillatory circuit forming a part of said oscillation generating means, and means connecting the output of said oscillation amplifying means and said oscillatory circuit for preventing feed-back, whereby self-oscillation in said oscillation amplifying means is avoided.

8. In a radio signaling system, an oscillation generating means including a closed oscillatory tank circuit and a plurality of parallelly connected vacuum tube enerators, an oscillation amplify ng system including a plurality of parallelly connected vacuum tube amplifiers for amplifying oscillations produced in said oscillation generating system, and a connection including a capacity element connecting the output of said osc llation amplifying system and said oscillatory circuit for preventing self-oscillation in said oscillation amplifying system.

9. In a radio signal ng system, a plurality of vacuum tube amplifiers each having their grid and filament members connected in parallel, said amplifiers being divided into a plurality of groups and having the plate members of the tubes associated with each of said groups connected in parallel, one of said groups of tubes form ng an oscillation generating means, a closed oscillatory tank circuit associated with said oscillation generating means, the second of said groups of said vacuum tubes forming an oscillation amplifying means for amplifying the oscillat ons produced in said oscillation generating means, and a capacity means between the output of said oscillation amplifying means and said closed oscillatory circuit for preventing self-oscillation in said oscillation amplifying means.

10. The combination in an amplifying sys tem comprising an electron discharge oscillation generator and an electron discharge grid control amplifier having its input circuit supplied with oscillations derived from the oscillator, of means for preventing the amplifier from generating oscillations comprising a coupling through a capacity from theoutput circuit of the amplifier to a point in the oscillation circuit of the generator, said capacity being so chosen with respect to natural capacity coupling between the output and input circuits of the amplifier and the.

point in the oscillation circuit to which it is connected as to impress upon the grid of the amplifier a potential substantially equal and opposite to that impressed thereon by reason of the natural capacity coupling between the output and input circuits of the amplifier.

11. The combination in an amplifying system comprising an electron discharge oscillation generator and an electron discharge grid control amplifier having its input circuit supplied with oscillations derived from the oscillator, of means for preventing the amplifier from generating oscillations comprising a coupling through a capacity from the output circuit of the amplifier to a point in the oscillation circuit of the generator.

12. The combination in an amplifying system comprising an electron discharge oscillation generator and an electron discharge grid control amplifier having its input circuit supplied with oscillations derived from the oscillator, of means for preventing the amplifier from generating oscillations comprising a coupling through a capacity from the output circuit of the amplifier to a point in the oscillation circuit of the generator, said coupling being made to a point in the oscillation circuit at which the potential is substantially one hundred and eighty degrees out of phase with the potential supplied to the grid of the amplifier.

13. In radio signaling apparatus, an electron discharge device oscillator, an amplifier for amplifying oscillations fed thereto by said device, and, an oscillation neutralizing circuit connecting the output circuit of said amplifier to a circuit of said electron discharge device for preventing the generation of energy of undesired frequencies.

14. An amplifying system comprising an electron discharge device oscillator having associated input and output circuits, an amplifier for amplifying oscillations fed thereto by said device, said amplifier having associated input and output circuits, and, capacity coupling means coupling one of the circuits of said amplifier with one of the circuits of said electron discharge device oscillator for preventing the generation of undesired oscillations.

In an ain'plifying system an election discharge device oscillator having a tunable I input circuit, an amplifier coupled to'said oleand; capacity coupling means coupling the v output circuit ofsaiclamplifier with'thecun-if I ableinput ci rcuit ofsaicl electron clischarge device; oscillator "for preventing the 'g enera tion ofspuriousoscillations 1 16. lnconibination, alplura'lity 'of pawl-c V leledelectron discharge devices producing oscillations of-a desired frequency, inputand' outp ut'circuits for. said paralleled electron 1 discharge clevieesfa. pluralityof'p'aralleled] I amplifiers for amplifying theoutput'of said parallel d electron discharge devices; and means coupling the amplifiers ancl clevices V for/preventing the generation of undesired V oscillations. c V- -517;'ln' coinbination, a plurality of paralleledc electron discharge devices producing; oscillations vofatdesired frequency, a tunable input circuit for saidparalleled devices, a

- plurality; of paralleled. amplifiers for ampli- I fyingvtheoutput said device'sg'ancl, a neua' .7

trializing. capacity connectioni coupling theoutpui; circuit of said amplifiers to the tunable input'ei'rcuit of saicldevices, for preventing thegeneration of spurious oscillations, :1- c 36"; 'FFRED HUTTON KROGER.

vice for amplifying the OlltPlltfOfSElid'dQVlCG l 

